The invention relates to a process for purifying alkoxylated fats by treatment with a solid substance, to alkoxylated fats obtainable by this process, and to the use thereof.
Alkoxylated fats are employed for a large number of purposes. One purpose, which is increasing in importance, is the use as constituent of the solvent for preparing solutions of active substances which are insoluble in water, especially drugs. For administration of drugs it is necessary in certain cases that the drugs are present in stable solutions, eg. when the drugs are to be infused.
EP 645 145 A discloses pharmaceutical formulations which consist of a solution of an antineoplastic active substance and of a solvent, with the solvent comprising alkoxylated fats as cosolvent or solubilizer. The pharmaceutical formulation is stabilized by addition of an acid or of a salt or by treatment of the alkoxylated fat with aluminum oxide, in particular owing to the fact that the carboxylate content is reduced to a particular level.
WO 94/12030 discloses that pharmaceutical formulations as described in EP 645 145 can be stabilized by adding particular acids, in which case the resulting pH must be below 8.1.
However, these prior art constituents of pharmaceutical formulations often do not yet meet the requirements to be met by such constituents in respect of the stability of the resulting formulation.